SUN VALLEY, Idaho – Brian Roberts is ready to take the entertainment world by storm.

With a giant pile of cash on hand since selling his stake in QVC, the cable king who runs Comcast is getting ready to make a big push into the media content business, sources say.

He may join bidding for the cable networks owned by Vivendi Universal, but sources say his ambitions appear to be far greater. He is looking at all options – and some believe he may go after Disney or MGM.

Roberts, whose company is the country’s largest cable operator, has become one of the key personalities at the Allen & Co. conference in the wake of his $7.9 billion sale of a majority stake in home shopping channel QVC to John Malone’s Liberty Media.

When that deal was announced last week, much of the initial focus was on what the sale meant for Malone’s interest in bidding for Vivendi Universal Entertainment.

But the story that has generated considerable buzz here at the Allen & Co. gathering of the world’s biggest media moguls is what Roberts will do with all that cash.

Roberts told reporters Wednesday night that Comcast will actively seek opportunities, rather than simply work to reduce its debt, as many published reports have predicted.

Roberts has met twice so far with Malone here – including an early morning breakfast meeting yesterday – and sources say Comcast is considering entering the fray for Vivendi.

Roberts would most likely partner with one of the current bidders to gain control of Vivendi’s cable networks USA and Sci-Fi.

“I’m sure they want them, but those are the assets everyone wants,” said one high-level media executive here.

But Vivendi isn’t the only possible deal brewing. With Comcast’s balance sheet fortified by the QVC sale – ratings agency Moody’s upgraded Comcast’s credit outlook to “positive” this week – the company is likely to make a big play in the near future, perhaps for Disney or MGM, sources say.

When Comcast completed its blockbuster $30 billion acquisition of AT&T Broadband last year and catapulted to the No. 1 spot among cable operators, many in the media industry predicted that eventually Comcast would become a full-fledged media giant, aggressively expanding into content.

But many said it would take time – perhaps five years – before Comcast would be ready.